Why are Clay Idols better than Acrylic and Plaster of Paris?

Studies on the impact of idol immersions carried out in places like Bhopal, Jabalpur and Bengaluru show several significant impacts like steep rise in concentration of heavy metals, dissolved solids, and acid content, and a drop in dissolved oxygen. Since these studies mostly centre around testing of water quality before and after immersions, the results reflect the cumulative effect of PoP, clay, chemical colours and other materials; there is no way to ascertain the exact role of PoP in water pollution as well as its larger impact on the environment.

Basic chemistry says that PoP is made by heating gypsum at temperatures in the range of 300°F. When it comes in contact with water, the material regains the form of gypsum. Since gypsum is a naturally occurring substance, and is used as a soil-conditioner to reclaim saline-sodic soils, it has been argued by idol-makers’ associations that it is harmless to the environment.

A test carried out by Shyam Asolekar, professor at the Centre for Environmental Science and Engineering at IIT-Mumbai, showed that these idols remain intact for several months in still water, as compared to clay idols which dissolve within 45 minutes. “The immediate and most observable impact of PoP idol immersion is that it makes the water cloudy,” says Avantika Chitnavis of Nagpur-based non-profit Nagpur Heritage Society. “Unlike clay, PoP idols take months to dissolve and the water remains that way for a long time after the festival is over.”

“Gypsum being natural material does not discount the fact that adding large quantities of it to water will raise its hardness and reduce its life-carrying capacity,” says Lolita Gupta of Eco-exist, Pune (her firm makes and sells clay idols of Ganesha). “It has been a common observation that a large number of fish deaths occur in water-bodies after immersions,” she says. “The only problem with these idols is the chemical paints used on them,” says Baliram Pawar, vice president of Ganesh Murtikar Sanghatana (association of idol makers) at Pen near Pune.

The place is one of the largest idol-making hubs in the state, “We have already shifted to environment-friendly poster colours, so there should be no environmental problems,” he says. Chitnavis, who has been organising workshop on eco-friendly idols in Nagpur every year for three years now, doubts the veracity of this claim. “In my work with eco-friendly colours, I found that water-based colours like food colours and natural dyes do not sit well on PoP idols because water reacts with PoP. The only paints that work on PoP are oil paints which are high in poisonous chemicals and heavy metals.” Also, poster colours also have chemical and heavy-metal content and are only fractionally less hazardous than oil paints.

The impact of these colours can be heavy. Studies on before and after immersion water quality show a disturbing rise in concentration of hazardous heavy metals like lead, mercury and cadmium post immersion. A 2007 study published in the Journal of Applied Sciences and Environment Management found the concentration of heavy metals in Bhopal’s Upper Lake rising by 750 per cent post immersion. A study conducted by the Central Pollution Control Board (CPCB) in Bengaluru revealed that post immersion, acid content and dissolved solid content in the water rose significantly. Presence of heavy metals like iron increased 10 times, while the presence of copper in sediments increased by 200 to 300 times. Water quality studies at Hyderabad, Bengaluru, Nagpur and Jabalpur show similar results.

This is why we at Rotary Green City encourage the use of Clay Ganesh Idols. They dissolve easily in the water, thus making rivers and ponds healthier. The clay wil mix in with the dirt, thus helping with the underwater ecosystem. The dissolved oxygen content will stay consistent, and so the various marine animals can thrive peacefully. On a religious note, There are references in the Puranas (mythological texts) that Ganesha was created from mud. Hence it is appropriate to use a Ganesh idol made of clay for ritualistic worship.

Src: https://www.downtoearth.org.in/news/how-harmful-is-pop-to-the-environment-42241